We have previously demonstrated that the phosphorylation of p65 at serine 536 was differentially recruited to selective promoters following cell activation. We have recently demonstrated that the distance between the site of p65 binding and the transcription start site of a particular gene determines if p65 needs to be phosphorylated on serine 536. The phosphorylation of p65 was not involved in the formation of an enhanceosome, where the recruitment of histone modifying enzymes to proximal promoters was required. These findings suggested that the phosphorylation of p65 and the cis-acting elements of the promoter regulate the various NFkB responsive genes. We are currently investigating the role of various phosphorylation sites of p65 in controling the chromatin architecture surrounding p65 responsive genes. We are also examining how the various IkB members regulate the nuclear translocation of phosphorylated p65. In addition to serine 536, the phosphorylation of serine 529 of p65 has been shown to regulate transcriptional activity. We are currently investigating the relationship between the phosphorylation of serines 529 and 536 in regulating the chromatin architecture. Furthermore, an alternative pathway has been described to activate the NFkB proteins and promote transcription. We are examining the role of p65 phosphorylation in controlling gene transcription induced by the alternative NFkB pathway.